DE3210985C3 - Non-contact electronic control for a sanitary fitting, especially a urinal - Google Patents

Description

The invention relates to a contactless electronic Control for a sanitary fitting, especially a Uri nal, with a microphone working according to the Doppler principle wave module, which ent a transmitting diode and a mixing diode holds, and with a receiving circuit, which on the off response signal of the mixing diode and the flushing the valve triggering signal generated.

In recent times, the contactless control has been more sanitary Fittings increasing by radar or microwave beams Gained meaning. The reason for this is the fact that the radar or microwave radiation (hereinafter only still spoken of microwave radiation) Tile and Kera can penetrate mic parts. Sender and receiver can do that forth invisible to the user, what opti and hygienic reasons, but also to protect against Vandalism is desirable.

Known controls of this type have a microwave module on, in which a transmitter diode and a mixing diode are integrated are. The microwave beam emitted by the transmitter diode lung is reflected by the user and reaches the mixing diode. If the user moves, the mixing diode generates due to the Doppler effect an output signal which then logically processed to trigger the water rinse becomes. Controls work according to the state of the art after a pure movement detection: as long as the mixing diode emitted signals at all, i.e. movements of a person but before the microwave module took place, the water remained flushing not triggered. Then if the signal of the mixing diode For a long time there was no electronics perceived that the user stepped away from the urinal; after a certain time delay the Water flush triggered.

Now it could happen with these known controls, that the user stood in front of the urinal for a long time without to move. The electronics then pulled the irri out of it to the conclusion that the user has already left, and incorrectly triggered a water flush.

BE-PS 886 078 is a motion detector in particular known for controlling doors. He points two mixed diodes arranged at a distance from one another, from their phase position with the help of a phase discriminator Get information about whether the user towards the mixed diodes, from the Mixing diodes away or across the mixing diodes goes. The evaluation circuit is set up that they are the controlled function, in particular opening a door, then suppressed when the Direction of movement of the user across the mixing diodes runs.

The object of the present invention is a touch loose electronic control of the type mentioned art to train that false triggers, be it by external Interferences, be it through incorrect interpretation of the incoming information can be reliably avoided.

This object is achieved by the following  characteristics solved:

• a) the microwave module is a double module with two mixing diodes, which are arranged at a certain geometric distance from one another, the phase relationship of the output signals S ₁ , S _{2 of} the two mixing diodes at approach and distance of the user from the microwave module being different;
• b) a phase discriminator is provided, to which the output signals S ₁ , S _{2 of} the mixing diodes are supplied and which emits an output signal E when the phase relationship between the signals S ₁ , S ₂ indicates a removal of the user from the microwave module;
• c) an evaluation circuit is provided, which the Flushing triggering signal T then generated when a be correct, minimal time integral of the signal E is present, which corresponds to a minimum duration of the signal E and an indication making sure that a user is actually off the tap has stepped away.

By using a double module according to the invention with two mixing diodes, considerably more information is available Processing available than with known controls. While this is the approach or the distance of the Be user could not differentiate, this will be with the front lying invention possible. The logical condition that must be given to trigger the water rinse is now no longer the absence of a signal from the mixing diaries the, but the presence of a signal E with a be agreed minimal time integral. The electronics he knows that the user steps away from the urinal or from Microwave module remember that in this case a special long-lasting signal E occurs. The water rinse will then in a manner known per se, if necessary in certain ter time delay, triggered.

Microwave double modules are in and of themselves in this way known that within a unit two the required Chen spaced mixing diodes and a transmitter diode are provided. However, the double module is preferred designed so that the transmitter diode within the microwave lenmoduls takes over the function of a mixing diode, for what it is preceded by a low resistance. On this simplifies the mechanical structure (hollow conductor) and the electrical circuitry considerably.

In a simple case, the evaluation circuit comprises:

• a) a first integrator to which the signal E is supplied;
• b) a first comparator to which the output signal of the first integrator and a reference voltage and which generates an output signal when the off output signal of the integrator the reference voltage increases;
• c) a reset circuit that the integrator after generation of a signal T resets to the output voltage 0.

The integrator is used to record the minimum Triggering of the water flush effecting time integral of the signal E, the size of which may be adjustable Reference voltage is specified. It is not required so that the time integral through an uninterrupted signal E builds up. Also a repeated, shorter approach signal E can trigger water flushing to lead. This corresponds to the practical situation since the user is not necessarily in one hanging movement, but possibly "jerky" the reception area of the microwave module removed.

Depending on the type of scarf that further processes the signal T. device can use the output signal of the comparator directly be det. However, the output of the Kompara is preferred tors connected to the input of a pulse shaper that the Signal T generated. This signal T can then in and for are known to be used as a trigger signal; in particularly simple cases can also directly result from this Amplifier can be controlled, which the solenoid of the What serventils energized.

The reset circuit can be a direct connection between the Output of the pulse shaper and the reset input of the In include tegrators. This means that with every release the water rinse, i.e. every time a signal T occurs, the integrator back to the output voltage 0 is provided and then ready for a new rinse cycle.

According to a further feature of the invention, the phase discriminator generates an output signal A when the phase relationship between the signals S ₁ , S ₂ indicates an approximation of the user. In this way, more precise information about the movement of the user is available, which can be processed in a variety of ways.

For example, the reset circuit can be a direct connection between the output of signal Pha send discriminator and the reset input of the integrator include. The integrator is not already on the way ten of a signal T, i.e. when the water rinse is triggered deferred, but only when a new Approach signal A is reported. In the period between last flush and the next approach signal A is the Electronics not "sharp", so not ready to trigger. Here is the influence of interference signals in the rest phases of the urinal turned off.

There is an alternative when processing signal A in that the reset circuit comprises an OR gate, the Output connected to the reset input of the integrator is the one input of the signal A and the other Input signal T is supplied. With this circuit variant, the integrator is always reset, if either a signal T is present, i.e. water rinsing is triggered, or an approach signal A is detected. The purpose of this measure is as follows: without the provision of the integrator with every signal A could turn out solve required minimum temporal integral of the signal E accumulate even when the user is in front of the mic wave module back and forth for a long time without it would actually step away completely. This will then turn out closed when the always like back and forth movements of the occurring signals A set the integrator to 0 defer so that the formation of the temporal integral of signal E starts again.

The "sharpening" of the electronics already described above by resetting the integrator using the signal A still has the disadvantage that it may already be very small signals A, which are randomly passing Per generated, undesirably cause the "sharpening". This is avoided  if the reset circuit includes:

• a) a second integrator, the input of which is signal A is fed;
• b) a second comparator, one input of which is off output signal of the second integrator and its other Output a second reference voltage is supplied;
• c) a second pulse shaper, the output signal of the Reset input of the first integrator is supplied;
• d) a reset circuit, the second integrator according to Er generation of a signal T to the output voltage 0 resets.

So here is a for processing signal A logic similar to that used to process the Signals E: only when a certain time integral of the signal A is present, which for an actual Her when a user steps into the urinal, it will Signal generated, which the first integrator on the off reset to 0, and so the electronics "sharpens".

Another, not on the reset of the signal E manufacturing integrators based sharpening can ge be designed so that the evaluation circuit also includes:

• a) a first flip-flop, the output with a first Entry of an AND gate and its entrance with the off gang of the first comparator is connected;
• b) a second integrator, the input with which the Si gnal A output of the phase discriminator verbun that is;
• c) a second comparator, one input of which is off output signal of the second integrator and its second Input a second reference voltage is supplied;
• d) a second flip-flop, the input of which is connected to the output of the second comparator and its output with a second input of the AND gate is connected;
• e) a pulse shaper connected downstream of the AND gate, the output signal of which is signal T,
  the two integrators and the two flip-flops being reset by the signal T.

The logic here is this: sharpening the electronics takes place in that an input of the AND gate then on a logical one is set when an approach signal certain minimal time integral is present, that is a user has actually approached the urinal. However, the water rinse is only triggered when also the second input of the AND gate with a logical One is occupied. This happens when the minimum le has accumulated temporal integral of the signal E, wel ches characteristic of the actual departure of the User.

According to a further feature of the invention, the first one Integrator has a plus and a minus input, the signals fed to the plus input as positive signals and the signals fed to the minus input as negative Signals are processed that the plus input of the first integrator, the signal E and signal A is fed to the minus input, taking care that the output signal of the first Integrators cannot become negative.

This circuit variant deals again with the Problem of back and forth movement of the user in front of the Uri nal. Instead of each approach as described above approximately A to the integrator again completely to 0 only the time accrued so far liche integral of the signal E around the "in between" falling time integral of signal A is reduced. The The output voltage of the first integrator thus corresponds to more precise way of the actual position of the user within the effective range of the microwave module.

The output voltage of the first integrator must not be nega tive, because otherwise the first approach of the user to the microwave module to a correspondingly strong negati ven output signal of the first integrator would lead that then by the distance signal E when the Be user would just be returned to 0. The The "switching threshold" of the first comparator would not be reached. This condition can be met, for example, by that the design of the first integrator has negative output tensions not allowed.

Alternatively, the minus input of the first integrator be an electronic switch upstream from the Signal T opened and from the output signal of the pulse shaper or the second flip-flop is closed. In this way se the signals A in the first approximation phase, be before the electronics is "sharp", not at the first Integrator.

The second integrator can also have a plus and a minus Possess input, whereby those fed to the plus input Signals as positive and those fed to the minus input Signals are processed as negative signals, the Plus input of the second integrator, the signal A and the Minus input the signal E are fed. The meaning of this Measure is that a user who is within the Range of action of the microwave module only back and forth moves, but does not actually approach the urinal that Electronics do not "sharpen". As with the process described above Processing of the signal E is already done here by the built the time integral of signal A in between resulting time integral of the signal E is subtracted.

A particularly advantageous embodiment of the phase dis criminators includes:

• a) a first all-pass phase shifter, the input of which a mixed diode output signal is supplied;
• b) a second all-pass phase shifter, the input of which other mixed diode output signal is supplied, wherein the phases caused by the second all-pass phase shifter shift by 90 ° larger than that of the first all pass-phase shifter;
• c) a first adder, the first input of which with the Output of the first phase shifter and its second Input with the output of the second all-pass phase shooter bers is connected.

The use of such a phase discriminator sets ahead that the geometric arrangement of the mixing diodes is a Phase difference of the output signals of 90 ° results.

Such a phase discriminator works independently of the respective occurring Doppler frequency, the  a function the speed of movement of the user, and also un depending on the amplitude of the signal that a function the distance between the user and the sensor. Without far This phase discriminator only produces re components Output signal E at times when the user from the urinal.

The phase discriminator expediently additionally comprises:

• d) a comparator, one input of which is the output signal of the first adder and its other input a Re reference voltage is supplied. This comparator determines the response threshold of the phase discriminator and thus the entire control circuit.

If both an output signal E of the phase discriminator when the user is removed as well as an output signal A is desired when the user approaches, the Phase discriminator additionally:

• e) an inverter whose input matches the output of the first All-pass phase shifter is connected;
• f) a second adder, the first input of which with the Output of the inverter and its second input with the Output of the second all-pass phase shifter is connected. In this case, a second comm parator provided, one input of which is the output signal of the second adder and its second input a reference voltage is supplied. This second com parator determines the switching threshold for the occurrence an output signal A.

Measuring the distance that the user is on the urinal to or from this can also be done on digital Ways take place when the phase discriminator with the frequency of the mixed diode output signals clocked output signals delivers. In this case, the ones mentioned in the above integrators described analog working circuits each by a correspondingly working counter put. The digital distance measurement has the advantage of Herer accuracy and is particularly independent of the Amplitude of the mixed diode output signals (as soon as the An switching threshold is exceeded).

Exemplary embodiments of the invention are described below the drawing explained in more detail; it shows

Fig. 1 shows schematically the block diagram of a non-contact urinal control;

FIG. 2 schematically shows the circuit arrangement for a first exemplary embodiment of the microwave module from FIG. 1;

Fig. 3 shows the circuit arrangement for a second embodiment example of a microwave module of Fig. 1;

Fig. 4-11 embodiments for the circuit arrangement of phase discriminators and out circuits for use in the block diagram of Fig. 1st

In Fig. 1, the block diagram of a non-contact urinal control is shown schematically. It comprises a microwave module 1 , in which a transmitter diode and two mixer diodes are accommodated. The microwave beams emitted by the transmitter diode are reflected by the user of the urinal system and strike the two mixing diodes. If the user is moving, the two mixing diodes each emit a signal S ₁ , S ₂ , the frequency of which is a measure of the speed of movement.

The two mixing diodes are arranged geometrically within the module 1 so that the phase relationship of their output signals S ₁ , S ₂ depends on whether the user is approaching or away. In terms of effectiveness, the two mixing diodes are preferably at a distance of λ / 4. In this case, one mixed diode signal S ₁ hurries ahead of the other mixed diode signal S ₂ when the user approaches 90 ° and lags behind the latter when the user is removed by 90 °.

The mixed diode signals S ₁ and S ₂ are each applied to an amplifier 2 and 3 , the outputs of which are connected to the two inputs of a phase discriminator 4 .

The phase discriminator 4 has two outputs. On the one hand, the signal A appears when the phase relationship between the mixed diode signals S ₁ and S ₂ indicates the user's approach to the microwave module. At the other output of the phase discriminator 4 , the signal E appears when the phase relationship between the signals S ₁ and S ₂ indicates the distance of the user from the microwave module 1 .

The output signals A and E of the phase discriminator 4 are fed to the two inputs of an evaluation circuit 5 and processed there logically.

The basic idea of the logic which the evaluation circuit 5 makes use of is as follows:

A sign that the user has actually stepped away from the urinal and is no longer there (still or with small-amplitude movements) is a certain minimum time integral of the signal E. However, it is not necessary that the time integral is built up by an uninterrupted signal E. The minimum time integral of the signal E required for triggering is experimentally determined and preset in the illustrated embodiment. The actual speed of movement of the user, which is expressed in the frequency of the mixing diodes signals S ₁ and S ₂ , is not processed for the sake of simplicity. In principle, however, it would be possible to make the minimum time integral of the signal E a function of the frequency of the mixed diode signals S ₁ and S ₂ , since the time it takes for the user to leave the sensitivity range of the module 1 is a function of Speed is.

The evaluation of the signal E can if necessary by the Signal A can be modified as detailed below is explained.

Has the evaluation circuit 5 recognized by a correspondingly long to the signal E that the user has stepped away from the urinal system, it outputs an output signal T to the valve driver circuit 6 . This contains the amplifiers, timing elements and possibly pulse shapers required for the operation of the solenoid valves, as is known per se.

In Fig. 2 the circuit arrangement of a known micro wave module is shown. It contains a transmission Gunn diode G and two mixing diodes M ₁ and M ₂ , which are located in the waveguides shown in dashed lines under the required geometric conditions. The output signal S ₁ is tapped at a parallel circuit consisting of the mixing diode M ₁ and a resistor R ₃ , which is connected via a resistor R ₁ to the stabilized supply voltage V _stab . In a corresponding manner, the output signal S _{2 is} tapped at a parallel circuit composed of the mixing diodes M ₂ and a resistor R ₄ , which was connected to the stabilized supply voltage V _stab via a counter R ₂ .

The novel double module shown in FIG. 3 is of considerably simpler construction than the module of FIG. 2 and serves the same purpose.

In addition to the transmitter Gunn diode G, it comprises only one mixing diode M; both are accommodated in waveguides shown in dashed lines un. The Gunn diode G thereby takes over the function of the mixing diode M ₁ from FIG. 2. For this purpose, it is connected via a resistor R ' ₁ to the supply voltage V _stab . This must be so low that the Gunn diode G remains vibratable. The output voltage S ₁ can then be tapped directly at the Gunn diode G.

Since - as mentioned - the Gunn diode G for this circuit serves as a mixing diode, must now be between it and the remaining mixing diode M for the required effect distance of λ / 4.

The signals S ₁ and S _{2 of} the circuits according to FIGS. 2 and 3 still contain undesired mixed frequency components which are removed in a known manner.

FIG. 4 shows a simple exemplary embodiment for the evaluation circuit 5 from FIG. 1.

The signal E, which indicates the user's departure, is at the input of the integrator 7 . The output signal of the integrator 7 , which grows linearly with the time duration of the signal E, lies at a first input of a comparator 8 . At the second input of the comparator 8 there is an optionally adjustable reference voltage V _ref , which is a measure of the desired minimum time integral of the signal E. If the output voltage of the integrator 7 exceeds the reference voltage V _ref , the comparator 8 outputs a signal to the pulse converter 9 . In the illustrated embodiment, it is a monostable circuit, the output signal T can be given directly to the solenoid valve amplifier in the simplest case. Alternatively, a known system of timers is triggered by the signal T.

The output of the pulse shaper 9 is also connected to a reset input R of the integrator 7 , so that the output signal of the integrator 7 is reset to 0 by the signal T.

The function of the contactless control just described (evaluation circuit according to FIG. 4 in the block diagram of FIG. 1) is as follows:

The user approaches the urinal and thus approaches the microwave module 1 . The phase position of the module output signals S ₁ , S ₂ is such that the phase discriminator 4 outputs an output signal A. This signal is no longer used in this simplest circuit variant.

Smaller back and forth movements of the user in front of the Uri nal cause the phase discriminator 4 alternately emits short-term signals A and E. Since the output voltage of the integrator 7 does not exceed the reference voltage of the comparator 8 , no signal T appears at the output of the pulse shaper. The user can also stand in front of the microwave module for any length of time without causing a false trigger. If the user finally steps away from the urinal, a signal E which lasts for a longer time appears at the input of the integrator 7 . This is highly integrated into an output signal of the integrator 7 , which exceeds the reference voltage V _ref . Now a signal appears at the output of the comparator 8 , which triggers the pulse shaper 9 . The resulting output signal T is further processed to actuate the solenoid valves in the water rinse and at the same time resets the integrator 7 to 0.

In this simplest embodiment, it can happen under unfavorable circumstances that if the user moves back and forth too long in front of the urinal, a sufficiently large output signal from the integrator 7 is finally integrated before the user actually steps away. This can be counteracted by allowing the output signal of the integrator to decay with a certain time constant, so that processes that took place very long ago are no longer taken into account. In this case it would be It may also be possible to forego the resetting of the integrator by the signal T. With this type of circuit, there is the possibility - however more theoretical - that the user "creeps" so slowly out of the effective range of the microwave module that the output signal of the integrator 7 never reaches the reference voltage V _ref and therefore no water rinsing is triggered.

A more elegant way of solving the problem associated with longer back and forth movements of the user in front of the urinal is shown in FIG. 5. In this circuit variant, the output signal A of the phase discriminator 4 indicating the approach of the user is now used. There is an input of an OR gate 10 , the output of which is connected to the reset input R of the integrator 7 . The signal T is fed to the second input of the OR gate 10 .

The function of this circuit variant is as follows:

If the user moves back and forth in front of the urinal, the integrator 7 is reset to 0 with each approach by the resulting signal A. The signals E built up before this point in time in the integrator 7 are therefore not taken into account. The output signal T appears only when the distance signal E has been applied to the integrator 8 for so long since the last proximity signal A that its output signal exceeds the reference voltage V _ref .

The integrator 7 is also reset after triggering the Impulsfor mers 9 by the signal T.

This reset by the signal T can also be dispensed with, as shown in FIG. 6. The starting point here is that before each new flushing of the urinal there is of course a new approach and thus a new signal A occurs. This circuit variant has the additional advantage that the electronics between the triggering of the last signal T and the next user approach is not "armed" and therefore cannot be triggered by interference.

The idea of "sharpening" the electronics by the approach signal A is consistently continued in the circuit variant according to FIG. 7. It is intended to prevent a small proximity signal, which does not yet represent a complete approach of a user, from "sharpening" the electronics.

The circuit branch shown in FIG. 7 below, which processes the signal E, largely corresponds to that according to FIG. 6. It in turn comprises an integrator 107 , a comparator 108 and a monostable circuit 109 as a pulse shaper for generating the signal T.

The integrator 107 has two inputs: a plus input, to which the signal E is applied, which is integrated upwards by the integrator, and a minus input, to which the signal A is applied, when an upstream electronic switch 114 is connected (This will be discussed further below).

The upper circuit branch in FIG. 7 is used to process the proximity signal A. It also comprises an integrator 111 , the output of which is connected to an input of a comparator 112 . At the second input of the comparator 112 there is a (possibly adjustable) reference voltage V _{R 2} . The output of the comparator 112 is connected to a pulse generator 113 (eg a monostable circuit), the output signal of which is fed to the integrator input R and the closing input of the electronic switch 114 . The switch 114 is opened by the output signal T of the monostable circuit 109 , which also resets the integrator 111 to 0.

To clarify the function of the circuit of FIG. 7, first consider the state after the completion of a rinsing cycle, that is to say after the occurrence of the last signal T: the output signal of the integrator 107 is greater than the reference voltage V _{R 1 of} the associated comparator; the monostable circuit 109 can only be triggered again after the integrator 107 has been reset. The circuit is therefore not "armed". The integrator 111 was reset by the previous signal T, which also opened the switch 114 .

If a user now approaches the urinal, a signal A appears at the plus input of integrator 111 , but not at the minus input of integrator 107 . If this lasts long enough, the output signal of the integrator 111 exceeds the reference voltage V _{R 2} . The comparator 112 triggers the monostable circuit 113 , the output signal of which closes the switch 114 and resets the integrator 107 . The electronics are now in their "armed" operating state.

If the person has only approached the urinal by chance and not sufficiently far, so that the monostable circuit 113 is not triggered, the output voltage of the integrator 111 is replaced by the signal E at the minus input, which occurs when the person steps away returned. In this way it is prevented that a plurality of successive volatile approaches, each of which could not in itself trigger the monostable circuit 113, lead to the undesired "sharpening" of the electronics.

If the electronics are now sharpened by resetting the integrator 107 and closing the switch 114 after a user approaches the urinal, the following occurs:

The output signal of the integrator 107 is the integrated difference between the signals E and A. When the user moves back and forth, this integrated difference is 0 or small; Even with longer periods of movement with small amplitudes, the electronics do not trigger (of course, not even when the user is completely in front of the urinal). Only when there is such an "excess" of the signal E over the signal A that the output signal of the integrator 107 is greater than the reference voltage V _{R 1} , does the monostable circuit 109 generate a signal T. This triggers the water flushing, the integrator 111 back and opens switch 114 . The electronics are now ready for the next rinse cycle.

In the circuit examples according to FIGS . 6 and 7, the "sharpening" of the electronics is based on the resetting of the integrators 7 and 107 by a signal A, without which the pulse shaper 109 cannot be triggered again. Another type of "sharpening" is shown in Fig. 8.

The lower circuit branch processing signal E again contains an integrator 207 with two inputs and a comparator 208 . At the plus input of the integrator 207 is the signal E, at the minus input the signal A. The output of the integrator 207 is connected to an input of the comparator 208 , the second input of which is supplied with a first reference voltage V _{R 1} . The output signal of the comparator 208 sets a flip-flop 215 , the output of which is connected to an input of an AND gate 216 . Whose output is in turn connected to a pulse shaper 209 , for example a monostable circuit, which - comparable to the circuit 9 and 109 in FIGS. 4-7 - supplies the signal T.

The upper, the signal A processing circuit also includes an integrator 211 , a comparator 212 and a flip-flop 217th These components are connected as well as their "counterparts" in the lower circuit branch, with the exception that the signal A is now at the plus input of the integrator 211 and the signal E is at the minus input. The output of the flip-flop 217 is connected to the second input of the AND gate 216 .

The signal T is fed to the reset inputs R of the integrators 207, 211 and the flip-flops 215, 217 .

To explain how this circuit works, let us first consider the state after the completion of a rinsing cycle. Here, the integrators 207, 211 and the flip-flops 215 and 217 are reset by the previous signal T. Both inputs of the AND gate 216 are "low", that is, on a logical "0".

If a user now approaches the urinal, a signal A is present at the plus input of the integrator 211 . If it moves away again before the output signal of the integrator 211 reaches the switching threshold V _{R 2 of} the comparator 211 , the output signal of the integrator 211 is reduced again by the signal E at the minus input.

The comparator 212 only turns on when a correspondingly large "excess" of the proximity signal A is integrated over the distance signal E. The flip-flop 217 is set in this case. A logical "1" now appears at the top of the AND gate 216 in the drawing. Since the lower input of the AND gate is "low", it does not switch through yet. However, the electronics are now "sharp" and are waiting for a sufficiently large distance signal E.

The during the above described "sharpening" phase at the minus input of the integrator 207. A signal present may be no negative output voltages lead 207 of the Integra tors. This can be achieved, for example, by designing the integrator 207 in such a way that no negative output voltages can occur. Alternatively - as in the exemplary embodiment according to FIG. 7 - an electronic switch can be placed in the supply line to the minus input of the integrator 207 , which opens by the signal T ge and is closed by the output signal of the flip-flop 217 .

As mentioned, the electronics are sharpened when the Be user has actually approached the urinal if thus a certain excess of the proximity signal over the distance signal is determined.

If the user moves back and forth in front of the urinal, this has no effect because of the effect of the integrator 207, which is acted upon in opposite directions by the signals A and E. It goes without saying that a complete standstill of the user does not result in a false trigger. Only when the user actually steps away from the urinal and thus generates a certain "excess" of the signals E over the signal A does the output voltage of the integrator 207 exceed the reference voltage of the comparator 208 . This switches through and sets the flip-flop 215 , whose output signal at the lower input of the AND gate 216 appears as a logic "1". Since both inputs of the AND gate are now high, this switches through and triggers the pulse shaper 209 . Its output signal T triggers the water rinse - if necessary with desired time delays - and resets the integrators 207 and 211 and the flip-flops 215 and 217 : the electronics are ready for the next cycle.

The examples above show how the through the use of the special microwave double module bare larger information to increase operational reliability contactless urinal controls can be used.

Fig. 9 shows an embodiment for the Phasendiskri minator 4 of Fig. 1, the only output E emits a signal when the phase position of the two Mischdiodensi signals S₁ and S₂ indicates a distance of the user from the urinal. At all other times, output E is at zero potential.

The signal S₁ is fed to a first all-pass phase shifter 15 , the output of which is connected to a first input of an adder 16 . In a corresponding manner, the signal S₂ is fed to a second all-pass phase shifter 17 , the output of which is connected to a second input of the adder 16 . The output signal of the adder 16 , which corresponds to the sum of its input signals, is fed to an input of a comparator 18 , at the second input of which a reference voltage V _R is present. The output of the comparator 18 corresponds to the output E of the phase discriminator 4 .

All-pass phase shifters are known per se. These are circuit networks that basically have the function of a phase shifter. The output signal is out of phase with the input signal by a certain amount. The peculiarity of these circuits is that the frequency characteristics of two of these phase shifters can be made parallel to a large frequency range. In other words: If one circuit shifts the phase position of its input signal by a frequency-dependent amount δ (f), the second circuit shifts the phase position of its input signal by the same frequency-dependent amount ε (f) plus a constant, frequency-independent amount ε. The circuit arrangement of FIG. 9 will now be designed so that the value ε overnight at the phase shift 15, 17 is 90 °, so that z. B. the phase shifter 17 shifts the phase of its input signal by 90 ° at all frequencies than the other ( 15 ).

To explain the operation of the circuit of Fig. 9 it is assumed that the phase position of the mixed diode output is signal S₁ ϕ. Then - with a suitable spatial arrangement of the two mixing diodes - the phase position of the mixing diode signal S₂ ϕ + 90 ° when the user approaches, and ϕ - 90 ° when the user moves away. For the phases of the output signal of the phase shifter 15 then results

η₁ = ϕ + δ (f)

for the phase position of the output signal of the phase shifter 17 results

η₂ = ϕ ± 90 ° + δ (f) + 90 °

The phase position η₂ is thus identical to η₁ when the user moves away from the urinal, and η₁ opposite when the user approaches. It follows directly that the output signals of the phase shifters 15, 17 overlap in the adder 16 in the same way when the user is removed, but cancel each other when the user approaches. This behavior of the circuit arrangement of Fig. 9 is independent of the frequency of the mixed diode signals S₁ and S₂, that is, the speed of movement of the user, and regardless of their amplitude, that is, the distance between the user and urinal.

By comparing the output signal of the adder 16 with the reference voltage V _R in the comparator 18 , the response threshold of the phase discriminator 4 and the entire ordered circuit is determined.

An exemplary embodiment of an all-pass phase shifter is shown in FIG. 10. This comprises three identical steps, except for the dimensioning of the circuit elements. Each stage contains a transistor T, the base of which forms the input of the stage. The collector of the transistor T is connected to the positive supply voltage via a resistor R, which is dimensioned the same for all stages, and the emitter is connected via a resistor R of the same size to the negative supply voltage. The collector of the transistor T is also connected via a - stage-specific dimensioned - capacitor C ₁ , C ₂ , C ₃ to the step output, which is also connected via a - stage-specific dimensioned - resistor R ₁ , R ₂ , R ₃ to the emitter of the transistor T is connected. The number of stages connected in series is determined according to the frequency range in which the circuit is to operate in the manner described. In Fig. 11 an embodiment of a phase discriminator 4 of Fig. 1 is shown, which emits both an output signal E when the user is away and an output signal A when the user approaches.

The two all-pass phase shifters 115, 117 , the adder 116 and the comparator 118 correspond completely to the components 15, 16, 17 and 18 of FIG. 9. They generate the user distance signal E in the manner described above.

Been added as compared to FIG. 9 in FIG. 11 is a rator In verter 119, a second adder 120 and a second Compa 121st The output signal of the all-pass phase shifter 115 is the first input of the adder 120 via the In verter 119 , ie leads with a phase shift of 180 °. The output of the all-pass phase shifter 117 is connected directly to the second input of the adder 120 . The operation of this adder 120 corresponds to that of the adder 116 , with the exception that the condition for the appearance of an output signal due to the inverter 119 is just reversed: Now the signals fed to the adder 120 are amplified when the phase position of the mixed diode output signals S 1, S₂ indicates an approach of the user; they cancel each other out when the phase position of the mixed diode output signals S₁, S₂ indicates a distance from the user.

By the comparator 121 , which compares the output signal of the Addie rers 120 with a reference voltage V _{R 2} (which does not need to match the reference voltage V _{R of} the comparator 118 ), the switching threshold for the appearance of an output signal A is again determined.

In the above-described embodiments of the evaluation circuit 5 in FIG. 1, it was assumed that the output signals A and E of the phase discriminator 4 are DC signals and that their time integral is a measure of the distance traveled by the user. The logical evaluation of these signals was essentially analog.

More precise results of the distance measurement, in particular regardless of the amplitude of the mixed diode output signals S₁, S₂ are can be used by using a digital Achieve evaluation logic. It should first be noted that due to the physical nature of the Doppler effect number of zero crossings of the signals S₁, S₂ a direct Measure of the distance traveled by the user.

The phase discriminator of Fig. 11 is suitable for such a digital evaluation, since it provides at its outputs A, E binary signals clocked with the frequency of the mixed diode output signals S₁, S₂. The circuit variants according to FIGS. 4 to 8 can then be switched to digital logic essentially simply by replacing the various integrators with correspondingly operating counters.

Claims (19)

1. Non-contact electronic control for a sanitary fitting, in particular a urinal, with a microwave module operating according to the Doppler principle, which contains a transmitting diode and a mixing diode, and with a receiving circuit which responds to the output signal of the mixing diode and the flushing signal triggering the valve, characterized by the following features:

• a) the microwave module ( 1 ) is a double module with two mixing diodes (M ₁ , M ₂ ; G, M), which are arranged at a certain geometric distance from each other, where the phase relationship of the output signals (S ₁ , S ₂ ) the two mixing diodes (M ₁ , M ₂ ; G, M) are different when the user approaches and moves away from the microwave module ( 1 );
• b) a phase discriminator ( 4 ) is provided, to which the output signals (S ₁ , S ₂ ) of the mixing diodes (M ₁ , M ₂ ; G, M) are supplied and which emits an output signal E when the phase relationship between the signals (S ₁ , S ₂ ) indicates removal of the user from the microwave module ( 1 );
• c) an evaluation circuit ( 5 ) is provided which generates the signal (T) which triggers the water rinse when there is a certain minimum time integral of the signal (E) which corresponds to a minimum duration of the signal (E) and is an indication of this, that a user has actually stepped away from the fitting.

2. Control according to claim 1, characterized in that the transmitter diode (G) within the microwave module ( 1 ) takes over the function of a mixing diode, for which purpose a low-resistance resistor (R ' ₁ ) is connected upstream. 3. Control according to claim 1 or 2, characterized in that the evaluation circuit ( 5 ) comprises:

• a) a first integrator ( 7; 107; 207 ) to which the signal (E) is supplied;
• b) a first comparator ( 8; 108; 208 ), to which the output signal from the first integrator ( 7; 107; 207 ) and a first reference voltage (V _ref , V _{R₁) is} supplied and which generates an output signal when the output signal of first integrator ( 7; 107; 207 ) exceeds the reference voltage (V _ref ; V _R₁ );
• c) a reset circuit which resets the integrator ( 7; 107; 207 ) after generating a signal (T) to the output voltage 0.

4. Control according to claim 3, characterized in that the output of the comparator ( 8; 108; 208 ) is connected to the input of a pulse shaper ( 9; 109; 209 ) which generates the signal (T). 5. Control according to claim 4, characterized in that the reset circuit comprises a direct connection between the output of the pulse shaper ( 9; 209 ) and the reset input (R) of the integrator ( 7; 207 ). 6. Control according to one of the preceding claims, characterized in that the phase discriminator ( 4 ) generates an output signal (A) when the phase relationship between the signals (S ₁ , S ₂ ) indicates an approach of the user. 7. Control according to claim 6 when referring to claim 3, characterized in that the reset circuit a direct connection between the signal (A) emitting output of the phase discriminator ( 4 ) and the reset input (R) of the integrator ( 7 ) includes 8. Control according to claim 4, with reference to claim 3, characterized in that the reset circuit comprises an OR gate ( 10 ), the output of which is connected to the reset input (R) of the integrator ( 7 ), the sen the input (A) and the other input the signal (T) is fed to one input. 9. Control according to claim 6 when referring to claim 3, characterized in that the reset circuit comprises:

• a) a second integrator ( 111 ), the input of which is fed the signal (A);
• b) a second comparator ( 112 ), one input of which is the output signal of the second integrator ( 111 ) and the other input of which is supplied with a second comparison voltage (V _R₂ );
• c) a second pulse shaper ( 113 ), whose output signal is fed to the reset input (R) of the first integrator ( 107 );
• d) a reset circuit, which resets the second integrator ( 111 ) after generation of a signal (T) to the output voltage 0.

10. Control according to claim 6 when referring to claim 3, characterized in that the evaluation circuit additionally comprises:

• a) a first flip-flop ( 215 ), the output of which is connected to a first input of an AND gate ( 216 ) and the input of which is connected to the output of the first comparator ( 208 );
• b) a second integrator ( 211 ) whose input is connected to the signal (A) output of the phase discriminator ( 4 );
• c) a comparator ( 212 ), one input of which is the output signal of the second integrator ( 211 ) and the second input of which is supplied with a second comparison voltage (V _{R 2} );
• d) a second flip-flop ( 217 ), the input of which is connected to the output of the second comparator ( 212 ) and whose output is connected to a second input of the AND gate ( 216 );
• e) a pulse shaper ( 209 ) connected downstream of the AND gate ( 216 ), the output signal of which is the signal (T), the two integrators ( 207, 211 ) and those in the flip-flops ( 215, 217 ) by the signal ( T) be put back.

11. Control according to claim 6, characterized in that the first integrator ( 107; 207 ) has a plus and a minus input, the signals to be passed to the plus input as positive and the signals to be fed to the minus input as negative signals are processed; that the plus input of the first integrator ( 107, 207 ) is supplied with the signal (E) and the minus input with the signal (A), taking care that the output signal of the first integrator ( 107; 207 ) does not become negative can. 12. Control according to claim 11, characterized in that the design of the first integrator ( 107; 207 ) does not allow negative output voltages. 13. Control according to claim 11 and with additional Rückbe relationship to claim 9 or 10, characterized in that the minus input of the first integrator ( 107 ) is connected upstream of an electronic switch ( 114 ) which is opened by the signal (T) and by the output signal the pulse former ( 113 ) or the second flip-flop ( 217 ) is closed. 14. Control according to claim 9 or 10, characterized in that the second integrator ( 211 ) has a plus and a minus input, the signals supplied to the plus input as positive signals and the signals supplied to the minus input as negative signals are processed, and that the plus input of the second integrator ( 21 ), the signal (A) and the minus input, the signal (E) are supplied. 15. Control according to one of the preceding claims, characterized in that the geometric arrangement of the mixing diodes results in a phase difference of the output signals S₁, S₂) of 90 ° and that the phase discriminator ( 4 ) comprises:

• a) a first all-pass phase shifter ( 15 ), the input of which is a mixed diode output signal (S₁);
• b) a second all-pass phase shifter ( 17 ), the input of which leads to the other mixed diode output signal (S₂), the phase shift caused by the second all-pass phase shifter ( 17 ) being 90 ° greater than that of the first all-pass phase shifter ( 15 ) is
• c) a first adder ( 16 ), the first input of which is connected to the output of the first all-pass phase shifter ( 15 ) and the second input of which is connected to the output of the two th all-pass phase shifter ( 17 ).

16. Control according to claim 15, characterized in that the phase discriminator ( 4 ) additionally comprises:

• d) a comparator ( 18 ), one input of which is the output signal from the first adder ( 16 ) and the other input of which a reference voltage (V _R ) is supplied.

17. Control according to claim 15 or 16, characterized in that the phase shifter ( 4 ) additionally comprises:

• e) an inverter ( 119 ), the input of which is connected to the output of the first all-pass phase shifter ( 115 );
• f) a second adder ( 120 ), the first input of which is connected to the output of the inverter ( 119 ) and the second input of which is connected to the output of the second all-pass phase shifter ( 117 ).

18. Control according to claim 17, characterized in that the phase discriminator ( 4 ) additionally comprises:

• g) a second comparator ( 121 ), one input of which is supplied with the output signal of the second adder ( 120 ) and the second input of which is supplied with a reference voltage (V _{R 2} ).

19. Control according to one of the preceding claims, characterized in that the phase discriminator ( 4 ) with the frequency of the mixed diode output signals (S₁, S₂) outputs GE clocked output signals (A, E) and that each integrator by a correspondingly operating counter sets is.